Process of making copper-containing monoazo dyestuffs



acid on ma for exam 1e corres nd to one of the fol- 2,144,104 f P, V

PROCESSOFMAKINGCOPPER-CONTAINING MoNoAzo DYESTUFFS 5 Hans Ruckstuhl, Basel, an Walter Wehrli, Riehen, Switzerland, assignors to Sandoz A. G., Basel, Switzerland, a Swiss firm No Drawing. Application July 3,1952, Serial No. 297,178

6Claims. or. 260-151 --N=N I No, -,N=N' 'a The present invention relates to new copper-containing 0m l g a monoazo dyestulfs and intermediates and to the preparation thereof. l i 4 I i SO H According to the present invention, briefly stated, the N NGCHS N O new products are obtained by subjecting aminoazo dyeg i stuffs which correspond to the formula 7 I n.o2s.o V 1 =N 0 H, N=N-Q1Bt OiH 01H nms v NH: Q' Q-son1 I I l whereinRc'lenotesa'n organic radical, onexdenotes hydro- H 1 gen, halogen, lower'alkyLlower alkoxy or nitro, the 5 v 3 other x being a sulfonic acid group, to the action of V g 7 1 1 t nitrous acid, whereby the amino group is replaced by the 2 hydroxy group, treating the thus-obtained hydroxyazo The replacement 0f the ammo group by the hydroxy dyestufl? with a copper'salt in the presence'of an oxidizing m the mmal m dyestufl5 1s efiected wlth agent and subsequently with a saponifying agent to split especlal ease by addmg 111mm to aynfiutral or Very 1 the sulfonic acid ester group weakly alkaline aqueous solution of the aminoaao dyestufi,

The resulting w coppepcbmaining lmonoazo deriva and then runmng the solution mto a dilutemmeral acid.

s correspond to f l v p 40 Afterstirring for several hours, a substantially quantita- HO tive yield of hydroxyazq dyestufi is obtained.

Coppering of the latter is advantageously carried out in aqueous solution with an inorganic or organic copper salt in the presence of anoxidizing agent. The resultant copper complex compounds are derivatives of 2'-hydroxybenzene-1,1'-azo2-hydroxy-riaphthalene. The saponificaf tion of the sulfonic acid ester group is carried out after the oxidative coppering, preferably in alkaline medium. I The following examples illustrate the invention, but are not intended to be restrictive thereof. Parts are parts by weight, percentages arepercentages by weight; temperatures are in degrees centigrade.

wherein, as in the initial aminoazo dyestufi, one x denotes hydrogen, halogen, lower alkyl, lower alkoxy or nitro, the other x being a sulfonic acid group. They are par- 1 ticularly valuable as coupling components and, because a Example 1 of their capability of coupling readily with diazo com- 21 Parts f h di lt f h i o dyestufi pounds of most diverse character, serve for the preparaf h f rmula tion of a wide variety of disazo and polyazo dyestuffs.

The aminoazo dyestufis, utilized as starting materials RAID-028.0 in the present invention, are readily accessible compounds. a The moiety R, the organic radical of the sulfonic acid I ester group, may be of widely different character; thus, do for example, R may be a radical of the composition H0;

- CHz-CH: Q g Ca *4? n, \om-ofi 03H or em The moiety Q are dissolved in 1000 parts of hot waterand then there is added to the resultantjsolution aconcentrated aqueous alkyl, lower alkoxy or nitro and the other x is the sulfonicf Asher- 3, i M solution of 8.} parts of sodium'nitrite. The hot solution is then run into a, mixture of 35 parts of concen trated hydrochloric acid and 100 parts of water, the tem- H; perature beingmaintained at 10 by the-addition of ice. wherein by definition one x is hydrogen, halogen, lower The mixture is stirred overnight at room temperature '1- i to 30) and is then adjusted to neutrality with the aid 'of sodium carbonate; afterwhich the'dyestu'tf'is precipitated by the addition of sodium chloride to the reaction solution an is filtered off. a

For roxidativeffc oppering, Qthe lthus-obtainedn' dyestuff paste is "stirred into"500 parts'bf water at room terr1perature (20-30"). 50 parts of crystalline sodium acetate and 27.5 parts of crystalline copper sulfate are thenadded in the form of concentrated aqueous solutions, whereupon in the :course of one hour 180 parts of an aqueous hydro gen peroxide solution of 5% strength are added dropwise. The thus-obtained copper complex compound is isolated by' s'alting out, and'is'then heated to" 80-85. -'with dilute aqueous sodium hydroxide solution, whereby the methylbenzenesulfonic acid moiety is split DE. The resultant dyestufi; after. being precipitated by the'addition of acetic acid to the reaction solution, is filteredt otf and dried. It

is a darlg powder which dissolves in water in'the presence of sodium carbonate with violet coloration and in concentratedsulfuric acid with bluish red-coloration.

The'thus-obtained; dyestufi corresponds to the'formula Copper-sulfate as a coppering agent can'be replaced by copper acetate.

The identical product is. obtained if, while otherwise proceeding as,aforedescribed in ;,thistexample, the starting aminoazo dyestutf is replaced by 62.1 parts of the sodium salt of the aminoazo dyestuff of the formula idem -;-or.rby 60} partspithesodium saltbfithe aminoazoirdye rtstuff of the'rformula Qoso stands for the 0- or p-methylated compounds. In all cases, the sodium salt of themethylbenzene-sulfonic acid ester ofthe aminoazoldyestiitfgmay, withoutmbtherwise deviating from'thedescribed procedure and while obtainingthe identical product,.be replaced by an equivalent amount ofthesodium saltbf lthe benzenesjulfonic acid ester or of the ethane-sulfionic acid ester orof the methzane-sulfonic acid ester or of the cyclohexanc-sulfohic acid ester.

The monoazo dyestuffs obtainedin analogous manner 'fromthe aminoazo' dyestuffs a, b and ,c, corresponding respectively to the formula:

150 parts of water are added dropwise.

Example? 60.7 pans of the sodium salt ofthe dyestufi of the formula Omen HOrS NH:

are dissolved in 1000 parts of hot water, and then a concentrated aqueous solution of 8.3 parts of sodium nitrite is added. The hot solution is run" into a mixture of 35 parts of concentrated hydrochloric acid and 100 parts of "water, the temperature being maintainedat by the The mixture is stirred overnight at room addition of ice. temperature (20-30) and is then adjusted to neutrality with the aid of sodium carbonate, and the dyestufi is precipitated by the addition of sodium chloride to the reaction solution and is then filtered ofi. I

For oxidative coppering, the thus-obtained dyestufi paste is stirred at room temperature (2030)f"into 500v parts of water. 50 parts of crystalline sodium acetate and 27.5 partsrof crystalline copper sulfate are then added in the form of concentrated aqueous solutions and then, in the course of one hour, parts of an aqueous hydrogen peroxide solution of 30% strength diluted with The thusobtained copper complex compound is isolated by salting out and then heated to 80-85 with aqueous potassium hydroxide solution, whereby;benzene-sulfonicacid is split off. Acetic acid isthen added to the reaction solution and the thus-precipitated dyestufljis filtered 0E and dried. It is a dark powder which dissolves in water in the presence of sodium carbonate with violet coloration and in vconcentratedsulfonie acid with bluish red coloration.

The thus-obtained dyestufi corresponds to'the' formula In strictly analogous manner, the aminoazo dyestufis of the formula a of the formula H O aSmNH:

can be converted into the corresponding copper complex compounds. Instead of copper sulfate there can be used copper ch1oride,. copper formiate or copper acetate.

Example 3 57.3 parts of the sodium salt of the aminoazo dyestulf Botswana are dissolved in 1000 parts of hot water, and then a concentrated aqueous solution of 8.3 parts of sodium nitrite is added. The hot solution is run into a mixture of 35 parts of concentrated hydrochloric acid and parts of water, the temperature being maintained at 10 by the addition of ice. The mixture is stirred overnight at room temperature (20-30) whereupon it is adjusted to neutrality with sodium carbonate, and the dyestutf precipitated by the addition. of an alkali metal salt to the reaction solution and then filtered oif.

For oxidative coppering, the thus-obtained dyestufi paste is stirred into 500 parts of water at room temperature (20-30). 50 parts of crystalline sodium acetate and 27.5 parts of crystalline copper sulfate in the form of ="concentra'ted aqueous vsolutions are then added, followed by the .dropwise addition in the course of an hour' of parts of a 5% aqueous hydrogen peroxide solutionlt The 27 thus-obtained copper complex componndtis zprecitated by the addittion of sodium chloride to the coppering solution, filtered off with the aid ofnsuct-ion and then heated to 80-85 with dilute aqueous sodium hydroxide solution, whereby ethanesulfonic acid is-split-mfi. The resultant dyestuflf, .rprecipitated by the addition of acetic acid to the :reaction SOlUliOIlg lS filtered off and dried. It is a dark powder'which dissolves in water in the presence of sodium carbonate with violet coloration and in concentrated sulfonic acid with bluish red, coloration, and

corresponds to the formula OaH In strictly analogous manner, the aminoazo dyestufis of the formula Q-ocnn r" 01H can be severally converted into the copper com'plex compound of 2'-hydroxybenzene-1,l-azo-2-hydroxynaphthalene.

By replacing the ethaneorzmethylbenzene-sulfonic acid of the aminoazo dyestufls of the present example by the equivalent amount of the methane-, cyclohexyl-,

benzeneor any other readily accessible sulfonic acid ester, the same productstresult.

Copper sulfate as av coppen'ng agent can be replaced by another inorganic or organic copper salt, such as copper chloride, copper formiate or copper acetate. The

saponification of the coppered dyestiitfs in order to split ofibthe. organic, .sulfonic acid radicalmcaniber'efieetedawith 1 potassiumI hydroxide z: solution 1 :instead sof t-zsodium -hyzdtoxide .solution.

lwmol'59f,,thet-omen-containing.tmonoazoz dyestufi of the formula Hogs- OaH L according to Example 1, is coupled with the intermediate -pr epared zfrom. Lmol, o;tetrazotized 3t,3',.-.dimethoxy-4,4'-

. .diamino-,l,1f,-diphen-ylandal rmoliof lrhydroxynaphtha- :-l.ene-3,6'-disulf0nicacid. I-ilhemresultant dyestuff,;is.;subi edato" a demethylating-coppering, (c, .g.: .according to ,theprocess; describedrtin U.;S.' Patent, No. 2,529,527), wherebyjt' isconvertedtintolthe complex compound: of, the formula =whichdyes cotton and fibers of regenerated c'e'llulosein "fast marine-blue shadesysee also copending U9 S.- Patent -No." 2-,644,8l2-,sgranted July 7; 1953.

- accordingto'Example' 2', is coupled with'thegintermidiate prepared from 1 mol of tetrazotized 3,3-dimthoxy'-4,4'- diamino-l,1'-diphenyl and 1 mol of l-hydroxynaphhtalene-3,6-disulfonic acid. The resultant dyestuff is subjected to a demethylating coppering (e.-.g. according to the process described in U. S.-'Pat. 2,529,527), whereby it is converted into the complex compound of the formula whichzglyes cottonaand'zfibers of regenerated cellulose in fast marine-blue shades; see also copending U. S. Patent No. 2,644,812, granted July 7, 1953.

f 13,744,104 "9 i 10 H p t fExampleo t anioxidizingagent and .subseguently with a saponifyin'g' 1 mol of he g-oppepcomainingmnofio dyesmfi of agent to spht 03 the sulfonlcacid methylphenyl ester the formula group Y 3. A process of preparing a copper-containing mono- H 5 azo compound, comprising the steps of replacing the amino group by the hydroxy group in the aminoazo dyestuff corresponding to the formula N HI 0m 30,9- NH: according to Example 3, is coupled with the intermediate 7 v 4, prepared from 1 mol of tetrazotized 3,3-dimethoxy,4'- N @5011; diamino-1,1-diphenyl and 1 mol of l-hydroxynaphtha- 7 Q Q by means ot nitrous acid," treating the thus-obtained hydroxyazo' dyestuif' with a copper salt in the presence of lene-3,8-disulfonic acid. The resultant dyestufi is subjected to a demethylating coppering (e. g. according to the process described in U. S. Pat. No. 2,529,527), whereby it an oxidizing agent and subsequently with a saponifying is converted into the complex compound of the formula agent to split off the sulfonic acid phenyl ester group.

4. A process of preparing a copper-containing monoazo compound, comprising the steps of replacing the amino group by the hydroxy group in the aminoazo dyestutf corresponding to the formula which dyes cotton and fibers of regenerated cellulose in fast marine-blue shades; see also copending U. S. Patent No. 2,644,812, granted July 7, 1953.

Having thus disclosed the invention, what is claimed is: 1. A process of preparing a copper-containing monoazo compound, comprising the steps of replacing the amino group by the hydroxy group in an aminoazo dyestuif corresponding to the formula 40 R.O2$.O

HOiS NH:

ran-@011. H0 8 NH 7 l i 01H wherein R stands for an organic radical, one x stands for by means of nitrous acid, treating the thus-obtained hydroxyazo dyestufl? with a copper salt in the presence of an oxidizing agent and subsequently with a saponifying agent to split oil the sulfonic acid ethyl ester group.

a member selected from the group consisting of hydrogen, halogen, lower alkyl, lower alkoxy and nitro, the other it being a sulfonic acid group, by means of nitrous acid, treating the thus-obtained hydroxyazo dyestufi with a copper salt in the presence of an oxidizing agent and sula sequently with a saponifying agent to split off the sulfonic 5. A process of preparing a copper-containing monoazo compound, comprising the steps of replacing the amino group by the hydroxy group in the aminoazo dyestufi corresponding to the formula acid ester group. CHI

2. A process of preparing a copper-containing monoazo compound, comprising the steps of replacing the amino group by the hydroxy group in the aminoazo dyestufi corresponding to the formula CH: 3033 NH! OsH by means of nitrous acid, treating the thus-obtained hydroxyazo dyestuff with a copper salt in the presence of an oxidizing agent and subsequently with a saponifying 0 agent to split off the sulfonic acid methylphenyl ester group.

by means of nitrous acid, treating the thus-obtained hy- 6. A process of preparing a copper-containing monodroxyazo dyestufi with a copper salt in the presence of 78 azo compound, comprising the steps of replacing the aminqxgrqupr byEthezhydmxyzgronprinxheaufinnamrdyewstuff eornespoixdingrmz zthefzformula droxyazo" dyestilff with a copper salt in the presence of .an oxidizing agentwanctsubsequently. with. a :saponifying References Cit'edfimthelile of this patent uU-NITED A STATES PATENTS Straub Dec. 15;1931 Wiedemann et a1 Dec. 1, 1936 Straub Aug. 17, 1937 M011 et a1 Mar. 15, 1938 Locke Apr. 1, 1947 Widmeretal .4. Dec. 2, 1952 Ruckstuhl et a1 July 7, 1953 FOREIGN"'PATENTS -..Canada Nov. 6, 1951 OTHER-1 REFERENCES "ii-Serf N0? 394,839; Mlieller (AEPIC. published L Apr. 

1. A PROCESS OF PREPARING A COPPER-CONTAINING MONOAZO COMPOUND, COMPRISING THE STEPS OF REPLACING THE AMINO GROUP BY THE HYDROXY GROUP IN AN AMINOAZO DYESTUFF CORRESPONDING TO THE FORMULA 